1. Field of the Invention
The present invention relates to processes for the production of butanediol, and more particularly relates to the production of butanediol from .gamma.-butyrolactone and hydrogen.
2. Description of Related Art
Broecker et al, U.S. Pat. No. 4,048,196, discloses a three step process for converting maleic anhydride or succinic anhydride to butanediol by (a) hydrogenating maleic anhydride or succinic anhydride in the presence of .gamma.-butyrolactone over a catalyst containing nickel, to give .gamma.-butyrolactone, (b) removing the water formed during the hydrogenation by separating .gamma.-butyrolactone and water from succinic anhydride by distillation, recycling succinic anhydride and separating .gamma.-butyrolactone and water by distillation, and (c) converting .gamma.-butyrolactone into butanediol and/or tetrahydrofuran over a catalyst containing copper and optionally zinc. Note that Broecker teaches the removal of the water from the .gamma.-butyrolactone prior to hydrogenation thereof to butanediol.